Carbon–Zinc (C–Zn) Technical Deep Dive — Electrochemistry, Geometry, Duty Cycle
Our C–Zn configuration builds on well-understood galvanic principles with a carbon (graphitic) cathode and a zinc anode operating in soil as the electrolyte. 1) Electrochemistry (neutral/alkaline soils) Anode (Zn): Zn(s) → Zn²⁺(aq) + 2 e⁻ Cathode (C) — oxygen reduction in aerated soils: O₂ + 2 H₂O + 4 e⁻ → 4 OH⁻ Implication: Carbon’s high surface area and catalytic sites lower cathodic overpotential, stabilizing output at IoT-level currents. 2) Electrode Geometry & Soil Interface • Surface area: Porous/graphitic carbon increases reaction area without large metal mass. • Spacing & path length: Keep ionic path short in moist, conductive layers; avoid gaps that raise ESR. • Aeration: Place carbon in oxygenated horizons; in waterlogged soils use shallower placement or micro-aeration channels.
3) Power Path & Conversion • DC–DC converter: high-efficiency step-up, quiescent current ≤ 10 µA; tune for peaks ≈ 300 mA (short video bursts). • Buffer sizing (unicode formula): E_day ≥ ΣE_events + E_standby + ΔE_temp (keep ≥ 20% margin for cold-weather derating).
4) Environmental Envelope (declared) Ambient −20…+45 °C (optimal −10…+35 °C). Works down to soil conductivity ~0.1 mS/cm; ≥ 0.2 mS/cm recommended. pH 6–8 preferred; log chloride-rich sites during pilots.
5) Validation Status Pilots in Estonia indicate improved output stability and lower polarization drift vs. Cu–Zn under matched loads. 10 s camera bursts (≈ 2–5 mWh) are feasible without compromising LoRa uplinks every 15–30 min. Interested in the C–Zn integration guide (layout, materials, QA)? DM for the engineering brief and pilot timelines. —
C–Zn — Technik: Zink-Anode, Kohlenstoff-Kathode (O₂-Reduktion) im Boden. Unicode-Formeln: Zn → Zn²⁺ + 2 e⁻, O₂ + 2 H₂O + 4 e⁻ → 4 OH⁻, E_day ≥ ΣE_events + E_standby + ΔE_temp. Basiszahlen: LoRa ~25 mJ/Sendung, 10-s-Clip ~3,0 mWh, PIR ~12 mJ. Einsatz −20…+45 °C (optimal −10…+35 °C), empfohlene Leitfähigkeit ≥ 0,2 mS/cm. Feldtests in bestätigen stabileren Output.
Our C–Zn configuration builds on well-understood galvanic principles with a carbon (graphitic) cathode and a zinc anode operating in soil as the electrolyte.
1) Electrochemistry (neutral/alkaline soils)
Anode (Zn): Zn(s) → Zn²⁺(aq) + 2 e⁻
Cathode (C) — oxygen reduction in aerated soils: O₂ + 2 H₂O + 4 e⁻ → 4 OH⁻
Implication: Carbon’s high surface area and catalytic sites lower cathodic overpotential, stabilizing output at IoT-level currents.
2) Electrode Geometry & Soil Interface
• Surface area: Porous/graphitic carbon increases reaction area without large metal mass.
• Spacing & path length: Keep ionic path short in moist, conductive layers; avoid gaps that raise ESR.
• Aeration: Place carbon in oxygenated horizons; in waterlogged soils use shallower placement or micro-aeration channels.
3) Power Path & Conversion
• DC–DC converter: high-efficiency step-up, quiescent current ≤ 10 µA; tune for peaks ≈ 300 mA (short video bursts).
• Buffer sizing (unicode formula): E_day ≥ ΣE_events + E_standby + ΔE_temp (keep ≥ 20% margin for cold-weather derating).
4) Environmental Envelope (declared)
Ambient −20…+45 °C (optimal −10…+35 °C). Works down to soil conductivity ~0.1 mS/cm; ≥ 0.2 mS/cm recommended. pH 6–8 preferred; log chloride-rich sites during pilots.
5) Validation Status
Pilots in Estonia indicate improved output stability and lower polarization drift vs. Cu–Zn under matched loads. 10 s camera bursts (≈ 2–5 mWh) are feasible without compromising LoRa uplinks every 15–30 min.
Interested in the C–Zn integration guide (layout, materials, QA)? DM for the engineering brief and pilot timelines.
—
C–Zn — Technik: Zink-Anode, Kohlenstoff-Kathode (O₂-Reduktion) im Boden. Unicode-Formeln: Zn → Zn²⁺ + 2 e⁻, O₂ + 2 H₂O + 4 e⁻ → 4 OH⁻, E_day ≥ ΣE_events + E_standby + ΔE_temp. Basiszahlen: LoRa ~25 mJ/Sendung, 10-s-Clip ~3,0 mWh, PIR ~12 mJ. Einsatz −20…+45 °C (optimal −10…+35 °C), empfohlene Leitfähigkeit ≥ 0,2 mS/cm. Feldtests in bestätigen stabileren Output.